PRODUCT INFORMATION
Pravastatin-RLTM TABLETS
Name of the Drug
Pravastatin sodium
Description
Chemical name: sodium (3R,5R)-7- [(1S,2S,6S,8S,8aR)- 1,2,6,7,8,8a- hexahydro-6hydroxy- 2-methyl-8-[(S)-2- methylbutyryloxy- 1-naphthyl]]-3,5- dihydroxyheptanoic acid.
Pravastatin sodium is an odourless, white to off-white, fine or crystalline powder. It is a
relatively polar hydrophilic compound with a partition coefficient (octanol/water) of 0.59
at a pH of 7.0. It is soluble in methanol and water (> 300 mg/mL), slightly soluble in
isopropanol, and practically insoluble in acetone, acetonitrile, chloroform and ether.
NaOOC
OH
HO
O
O
CH3
H
CH3
HO
CAS: 81131-70-6.
C23H35NaO7
MW: 446.52.
Pravastatin-RLTM tablets also contain as inactive ingredients:
Calcium hydrogen phosphate anhydrous, sodium starch glycollate, microcrystalline
cellulose, trometamol, dibasic sodium phosphate dihydrate, povidone, magnesium
stearate, ferric oxide.
Pharmacology
Pharmacodynamics
Actions
Pravastatin is one of a new class of lipid lowering compounds, the HMG-CoA reductase
inhibitors, that reduce cholesterol biosynthesis. These agents are competitive inhibitors
of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the enzyme
catalysing the early rate limiting step in cholesterol biosynthesis, conversion of HMGCoA to mevalonate.
Pharmacology
Pravastatin produces its lipid lowering effect in two ways. Firstly, as a consequence of its
reversible inhibition of HMG-CoA reductase activity, it affects modest reductions in
intracellular pools of cholesterol. This results in an increase in the number of low density
lipoprotein (LDL) receptors on cell surfaces and enhanced receptor mediated catabolism
and clearance of circulating LDL. Secondly, pravastatin inhibits LDL production by
inhibiting hepatic synthesis of very low density lipoprotein (VLDL), the LDL precursor.
Clinical and pathological studies have shown that elevated levels of total cholesterol
(total-C), low density lipoprotein cholesterol (LDL-C) and apolipoprotein B (a membrane
transport complex for LDL) promote human atherosclerosis. Similarly, decreased levels
of high density lipoprotein (HDL) cholesterol (HDL-C) and its transport complex,
apolipoprotein A, are associated with the development of atherosclerosis.
Epidemiological investigations have established that cardiovascular morbidity and
mortality vary directly with the level of total-C and LDL-C and inversely with the level of
HDL-C. In multicentre clinical trials those pharmacological and/or non-pharmacological
interventions that lowered total-C and LDL-C and increased HDL-C reduced the rate of
cardiovascular events (both fatal and nonfatal myocardial infarctions) and improved
survival. In both normal volunteers and patients with hyper-cholesterolaemia, treatment
with pravastatin reduced total-C, LDL-C, apolipoprotein B, VLDL-C and triglycerides
(TG) while increasing HDL-C and apolipoprotein A.
The effects of HMG-CoA reductase inhibitors on lipoprotein A, fibrinogen and certain
other independent biochemical risk markers for coronary heart disease are unknown.
Pravastatin is a hydrophilic HMG-CoA reductase inhibitor.
Clinical trials
Hypercholesterolaemia:
In controlled trials in patients with moderate hyper-cholesterolaemia, with or without
atherosclerotic cardiovascular disease, pravastatin monotherapy reduced the
progression of atherosclerosis and cardiovascular events (e.g. fatal and nonfatal
myocardial infarction) or death.
Pravastatin is highly effective in reducing total-C and LDL-C in patients with
heterozygous familial, familial combined and nonfamilial (nonFH) forms of hypercholesterolaemia. A therapeutic response is seen within one week, and the maximum
response usually is achieved within four weeks. This response is maintained during
extended periods of therapy.
A single daily dose administered in the evening is as effective as the same total daily
dose given twice a day. Once daily administration in the evening appears to be
marginally more effective than once daily administration in the morning, perhaps
because hepatic cholesterol is synthesised mainly at night.
In multicentre, double blind, placebo controlled studies of patients with primary
hypercholesterolaemia, treatment with pravastatin significantly decreased total-C, LDLC, and total-C/HDL-C and LDL-C/HDL-C ratios, decreased VLDL-C and plasma TG
levels, and increased HDL-C. Whether administered once or twice daily, a clear dose
response relationship (i.e. lipid lowering) was seen by one to two weeks following the
initiation of treatment (see Table 1).
Table 1 Primary hypercholesterolaemia study: dose response of pravastatin*
given once daily at bedtime.
Dose
10mg
20mg
40mg
Total
cholesterol
-16%
-24%
-25%
LDL
cholesterol
-22%
-32%
-34%
HDL
cholesterol
+7%
+2%
+12%
Triglycerides
-15%
-11%
-24%
*Percent change from baseline after 8 weeks
Pravastatin, in combination with diet, has been shown to reduce the incidence of cardiovascular events (e.g. fatal and nonfatal myocardial infarction). The mechanism
responsible for the beneficial effects of pravastatin in hypercholesterolaemic patients is
not known.
Atherosclerosis:
In the Pravastatin Limitation of Atherosclerosis in the Coronary Arteries (PLAC I) study,
the effect of pravastatin therapy on coronary atherosclerosis was assessed by coronary
angiography in patients with coronary disease and moderate hyper-cholesterolaemia
(baseline LDL-C range 3.4 to 4.9 mmol/L). In this double blind, multicentre, controlled
clinical trial in which 408 patients were randomised, angiograms were evaluated at
baseline and at three years in 264 patients. No statistically significant difference between
pravastatin and placebo was seen for the primary endpoint (per patient change in mean
coronary artery diameter), or for one of two secondary endpoints (change in percent
lumen diameter stenosis). For the other secondary endpoint (change in minimum lumen
diameter), statistically significant slowing of disease was seen in the pravastatin
treatment group (p = 0.02). Although the trial was not designed to assess clinical
coronary events, for myocardial infarction (fatal and nonfatal) the event rate was reduced
in the pravastatin group by a statistically significant margin (10.5% for placebo versus
4.2% for pravastatin, p = 0.0498).
In another three year, double blind, placebo controlled, randomised trial in patients with
mild to moderate hyperlipidaemia, the Pravastatin, Lipids and Atherosclerosis in the
Carotids (PLAC II) study, the effect of pravastatin therapy on carotid atherosclerosis was
assessed by B-mode ultrasound. No statistically significant differences were seen in the
carotid bifurcation, internal carotid artery, or all segments combined (the primary
endpoint); pravastatin did reduce the increase in wall thickness in the common carotid
artery (p = 0.02). Although the study was not designed to assess cardiovascular events
or mortality, the event rates were reduced in the pravastatin treatment group by
statistically significant margins for two combined endpoints: nonfatal or fatal myocardial
infarction (13.3% for placebo versus 2.7% for pravastatin, p = 0.018) and nonfatal
myocardial infarction or all deaths (17.1% for placebo versus 6.7% for pravastatin, p =
0.049).
Analysis of pooled events from PLAC I and PLAC II showed that treatment with
pravastatin was associated with a 67% reduction in the event rate of fatal and nonfatal
myocardial infarction (11.4% for placebo versus 3.8% for pravastatin, p = 0.003) and
55% for the combined endpoint of nonfatal myocardial infarction or death from any
cause (13.8% for placebo versus 6.2% for pravastatin, p = 0.009). Divergence in the
cumulative event rate curves began at one year and was statistically significant at two
years.
In consideration of the results of PLAC I and PLAC II, it is important to be aware of the
limitations of angiography in defining the extent and site of atherosclerosis plaque. Acute
coronary events tend to occur not at the site of severe stenosis, but at lesser stenoses
which are lipid rich and more prone to rupture. In addition, angiographic changes are not
properly validated endpoints to measure morbidity and/or mortality in patients with
atherosclerotic coronary artery disease associated with hypercholesterolaemia.
Prevention of coronary heart disease:
Pravastatin is effective in reducing the risk of coronary heart disease death (fatal
myocardial infarction and sudden death) and nonfatal myocardial infarction and
improving survival in hypercholesterolaemic male patients without previous myocardial
infarction.
The West of Scotland (WOS) study was a randomised, double blind, placebo controlled
trial among 6,595 male patients (45 to 64 years) with moderate to severe
hypercholesterolaemia (LDL-C = 4 to 6.6 mmol/L), a total fasting cholesterol > 6.5
mmol/L, and without previous myocardial infarction. Patients were treated with standard
care, including dietary advice, and either pravastatin 40 mg (n = 3,302) or placebo (n =
3,293) each evening for a median duration of 4.8 years. The study was designed to
assess the effect of pravastatin on fatal and nonfatal coronary heart disease. Significant
results (p < 0.05) are given in Table 2.
Table 2 West of Scotland study results
Endpoint
Events prevented per
1,000 patients treated with
pravastatin for 5 years*
19
Relative risk
reduction
Cardiovascular death
7
28%
Death (any cause)
9
22%
Coronary heart disease death or
nonfatal myocardial infarction
Coronary angiography
24
31%
14
31%
8
37%
Non-fatal myocardial infarction
Coronary angioplasty or coronary
artery bypass graft
31%
*Based on the Kaplan-Meier estimates of 5 years event rate
The effect on the combined endpoint of coronary heart disease death or nonfatal
myocardial infarction was evident as early as six months after beginning pravastatin
therapy.
There was no statistically significant difference between treatment groups in
noncardiovascular mortality, including cancer death (see Table 3 and Figure 1).
Table 3 West of Scotland study: effect of pravastatin on plasma lipids (mmol/L)
(intention to treat analysis)
Year 5 mean n =
1335
3.8
% Change mean*
LDL-cholesterol
Baseline mean
n=3302
5.0
HDL-cholesterol
1.1
1.3
10.1
Total cholesterol
7.0
5.8
-18.6
Triglycerides
1.9
1.8
-4.4
-24.9
*All changes statistically significant (p<0.001)
Figure 1
Myocardial infarction and unstable angina pectoris:
Pravastatin is effective in reducing the risk of a fatal coronary event and nonfatal
myocardial infarction in patients with a previous myocardial infarction and average
(normal) serum cholesterol, who are > 65 years of age and whose serum LDL
cholesterol is > 3.36 mmol/L. Pravastatin is effective in reducing the frequency of stroke
in patients with a previous myocardial infarction and average (normal) serum cholesterol.
Pravastatin is also effective in reducing the risk of total mortality, coronary heart disease
death, and recurrent coronary events (including myocardial infarction) in patients with
unstable angina pectoris.
In the Cholesterol and Recurrent Events (CARE) study the effect of pravastatin on
coronary heart disease death and nonfatal myocardial infarction was assessed in 4,159
men and women with average (normal) serum cholesterol levels (baseline mean total
C=209 mg/dL) (5.4 mmol/L), and who had experienced a myocardial infarction in the
preceding 3 to 20 months. Patients in this double blind, placebo controlled study
participated for an average of 4.9 years. Treatment with pravastatin significantly reduced
the rate of a recurrent coronary event (either CHD death or nonfatal myocardial
infarction) by 24 % (p = 0.003). This risk reduction was statistically significant in those
patients aged 65 years of age or older, and in those who demonstrated a serum LDL
cholesterol of > 3.36 mmol/L. The reduction in risk for this combined endpoint was
significant for both men and women. The risk of undergoing revascularisation
procedures (coronary artery bypass grafting or percutaneous transluminal coronary
angioplasty) was significantly reduced by 27% (p < 0.001) in the pravastatin treated
patients. Pravastatin also significantly reduced the risk for stroke by 32% (p = 0.032),
and stroke or transient ischemic attack (TIA) combined by 26% (p = 0.025). At baseline,
84% of patients were receiving aspirin and 82% were taking antihypertensive
medications. The comparison of the primary, secondary and tertiary endpoints for the
study are summarised in Table 4.
Table 4
Cholesterol and Recurrent Event (CARE) study: effect of pravastatin on CHD and
nonfatal MI
Event
Fatal CHD or
definite* nonfatal
Fatal CHD
Total mortality
Number (%a) of subjects
Pravastatin
(n= 2,081)
212 (10.4)
Placebo
(n = 2,078)
274 (13.3)
96 (4.9)
180 (8.6)
Avoided
eventsd
Risk reductionb Logrank
95% Cl
p-valuec
29
24 (9, 36)
0.003
119 (5.6)
7
20 (-5, 39)
0.104
196 (9.4)
8
9 (-12, 26)
0.366
a
Kaplan-Meier estimate of 5 year event rate.
Due to treatment with pravastatin by Cox proportional hazards model.
c
Mantel-Haenszel logrank p-value for between group difference of cumulative event curves
d
Per 1000 subjects on pravastatin over 5 years.
*
The term ‘definite’ refers to a report of a clinical MI by a clinical centre that meets that criteria of
MI described in the Manual of Operations as determined by review by the MI Confirmation
Centre.
b
In the Long-term Intervention with Pravastatin in Ischaemic Disease (LIPID) study, the
effect of pravastatin 40 mg daily was assessed in 9,014 men and women with normal to
elevated serum cholesterol levels (baseline total C = 4.0 to 7.0 mmol/L; mean total
C=5.66 mmol/L; mean total C/HDL C ratio = 5.9), and who had experienced either a
myocardial infarction or had been hospitalised for unstable angina pectoris in the
preceding 3 to 36 months. Patients with a wide range of baseline levels of triglycerides
were included (less than or equal to 5.0 mmol/L) and enrolment was not restricted by
baseline levels of HDL cholesterol. At baseline, 82% of patients were receiving aspirin,
76% were receiving antihypertensive medication, and 41% had undergone myocardial
revascularisation.
Patients in this multicentre, double blind, placebo controlled study participated for a
mean of 5.6 years (median = 5.9 years). Treatment with pravastatin significantly reduced
the risk for CHD death by 24% (p = 0.0004). The risk for coronary events (either CHD
death or nonfatal myocardial infarction) was significantly reduced by 24% (p < 0.0001) in
the pravastatin treated patients. The risk for fatal or nonfatal myocardial infarction was
reduced by 29% (p < 0.0001). Pravastatin reduced both the risk for total mortality by
23% (p < 0.0001) and cardiovascular mortality by 25% (p < 0.0001). The risk for
undergoing myocardial revascularisation procedures (coronary artery bypass grafting or
percutaneous transluminal coronary angioplasty) was significantly reduced by 20% (p <
0.0001) in the pravastatin treated patients. Pravastatin also significantly reduced the risk
for stroke by 19% (p = 0.0477). Treatment with pravastatin significantly reduced the
number of days of hospitalisation per 100 person years of follow-up by 15% (p < 0.001).
The prespecified subgroup (age, sex, hypertensives, diabetics, smokers, lipid
subgroups) analyses were conducted using the combined endpoint of CHD and nonfatal
myocardial infarction. The study was not powered to examine results within each
subgroup but formal testing for heterogeneity of treatment effect was undertaken across
each of the subgroups and no significant heterogeneity was found (p greater than or
equal to 0.08), i.e. a consistent treatment effect was seen with pravastatin therapy
across all patient subgroups and event parameters.
Among patients who qualified with a history of myocardial infarction, pravastatin
significantly reduced the risk for total mortality by 25% (p = 0.0016); for CHD mortality by
23% (p = 0.004); for CHD events by 22% (p = 0.002) and for fatal or nonfatal myocardial
infarction by 25% (p = 0.0008). Among patients who qualified with a history of
hospitalisation for unstable angina pectoris, pravastatin significantly reduced the risk for
total mortality by 26% (p = 0.0035); for CHD mortality by 26% (p = 0.0358); for CHD
events by 29% (p = 0.0001) and for fatal or nonfatal myocardial infarction by 37% (p =
0.0003).
The results of the LIPID study are shown in Table 5.
Table 5 Comparison of event rates by treatment group
(primary, secondary and tertiary efficacy measures) in the LIPID study.
Event
Number (%a) of subjects
CHD mortality
Pravastatin
(n= 4,512)
287 (5.3)
Placebo
(n = 4,502)
373 (6.4)
Total mortality
498 (8.9)
CHD mortality or
non-fatal MI
Stroke
All cause
Nonhaemorrhagic
Cardiovascular
mortality
Myocardial
revascularization
procedures
(CABG or PTCA)
Atherosclerotic
events
Fatal or non-fatal
MI
Avoided
eventsd
Risk reductionb Logrank
(95% Cl)
p-valuec
11
24% (12.35)
0.0004
633 (10.5)
16
23% (13.31)
<0.0001
557 (10.5)
715 (13.5)
27
24% (15.32)
<0.0001
169 (3.0)
154 (2.7)
204 (3.9)
196 (3.8)
9
11
19% (0.34)
23% (5.38)
0.0477
0.0154
331 (6.0)
433 (7.5)
15
25% (13.35)
<0.0001
584 (11.4)
706 (14.1)
27
20% (10.28)
<0.0001
1.116 (21.2)
1.352 (25.6)
44
21% (14.27)
<0.0001
336 (6.5)
463 (9.0)
25
29% (18.38)
<0.0001
a
Kaplan-Meier estimate of 5 year event rate.
Due to treatment with pravastatin by an unadjusted Cox proportional hazards model.
c
Stratified Mantel-Haenszel logrank P-value for between group difference of cumulative curves,
stratified by qualifying event (MI or UAP at randomization).
d
Per 1000 subjects on pravastatin over 5 years.
b
Solid organ transplantation:
The safety and efficacy of pravastatin treatment in patients receiving immunosuppresive
therapy following kidney and cardiac transplantation were assessed in two prospective
randomised controlled trials. Patients were treated concurrently with either 20 or 40 mg
pravastatin and a standard immunosuppresive regimen of cyclosporin and prednisone.
Cardiac transplant patients also received azathioprine as part of their immunosuppresive
regimen.
Plasma lipid levels were reduced in patients who received pravastatin. In the patients
who received pravastatin in these trials (n = 71) no significant increases in creatinine
phosphokinase or hepatic transaminases were observed and there were no cases of
myositis and rhabdomyolysis. However, there are limited data available on the incidence
of these adverse events in transplant patients and doctors should consider the risk of
myositis and rhabdomyolysis when prescribing pravastatin therapy for hyperlipidaemia in
transplant patients.
Pharmacokinetics
Pravastatin is administered orally in the active form. It is rapidly absorbed, with peak
plasma levels attained 1 to 1.5 hours following ingestion. Based on urinary recovery of
radiolabelled drug, the average oral absorption of pravastatin is 34% and absolute
bioavailability is 17%.
Pravastatin undergoes extensive first-pass extraction in the liver (extraction ratio 0.66),
which is its primary site of action, and the primary site of cholesterol synthesis and of
LDL-C clearance. Since it is excreted in the bile, plasma levels are of limited value in
predicting therapeutic effectiveness. Pravastatin plasma concentrations (including area
under the concentration time curve (AUC), peak (Cmax) and steady-state minimum
(Cssmin)) are directly proportional to the administered dose. Steady-state AUCs, Cmax
and Cssmin plasma concentrations showed no evidence of pravastatin accumulation
following once or twice daily administration of pravastatin tablets. Approximately 50% of
the circulating drug is bound to plasma proteins.
The plasma elimination half-life (t1/2) of pravastatin (oral) is between 1.5 and 2 hours.
Approximately 20% of a radiolabelled oral dose is excreted in urine and 70% in the
faeces. After intravenous administration of radiolabelled pravastatin to normal
volunteers, approximately 47% of total body clearance was via renal excretion and 53%
by nonrenal routes (i.e. biliary excretion and biotransformation). Accumulation of drug
and/or metabolites may occur in patients with renal or hepatic insufficiency, although, as
there are dual routes of elimination, the potential exists for compensatory excretion by
the alternate route. The major metabolite of pravastatin is the 3alpha-hydroxy isomer.
This metabolite has one-tenth to one-fortieth the HMG-CoA reductase inhibitory activity
of the parent compound.
Indication
As an adjunct to diet for the treatment of hypercholesterolaemia. Prior to initiating
therapy with pravastatin, secondary causes of hypercholesterolaemia (e.g. poorly
controlled diabetes mellitus, hypothyroidism, nephrotic syndrome, dysproteinaemias,
obstructive liver disease, other drug therapy, alcoholism) should be identified and
treated.
Patients with previous myocardial infarction including those who have normal (4.0 to
5.5mmol/L) serum cholesterol levels.
Patients with unstable angina pectoris (see Actions, Clinical Trials).
Contraindications
Hypersensitivity to any component of this medication.
Active liver disease or unexplained persistent elevations in liver function tests.
Use in pregnancy
Atherosclerosis is a chronic process and discontinuation of lipid lowering drugs during
pregnancy should have little impact on the outcome of long-term therapy of primary
hypercholesterolaemia. Cholesterol and other products of cholesterol biosynthesis are
essential components for fetal development (including synthesis of steroids and cell
membranes). Since HMG-CoA reductase inhibitors decrease cholesterol synthesis and
possibly the synthesis of other biologically active substances derived from cholesterol,
they may cause fetal harm when administered to a pregnant woman. Therefore, HMGCoA reductase inhibitors are contraindicated during pregnancy.
Safety in pregnant women has not been established. Although pravastatin was not
teratogenic in rats at doses as high as 1,000 mg/kg daily nor in rabbits at doses of up to
50 mg/kg daily, pravastatin should be administered to women of childbearing potential
only when such patients are highly unlikely to conceive and have been informed of the
potential hazards. If a woman becomes pregnant while taking pravastatin, it should be
discontinued and the patient advised again as to the potential hazards to the fetus.
Women of childbearing potential
Pravastatin should not be administered to women of childbearing age unless using
effective contraception and are highly unlikely to conceive, and have been informed of
the potential hazards. If the patient becomes pregnant while taking this class of drug,
therapy should be discontinued and the patient again advised of the potential hazard to
the fetus.
Precaution
Use with caution in the following circumstances
General
Pravastatin may elevate creatine phosphokinase and transaminase levels (see Adverse
Reactions). This should be considered in the differential diagnosis of chest pain in a
patient on therapy with pravastatin.
Homozygous familial hypercholesterolaemia
Pravastatin has not been evaluated in patients with rare homozygous familial
hypercholesterolaemia. In this group of patients, it has been reported that HMG-CoA
reductase inhibitors are less effective because the patients lack functional LDL
receptors.
Hypertriglyceridaemia
Pravastatin has only a moderate triglyceride lowering effect and it is not indicated where
hypertriglyceridaemia is the abnormality of most concern (i.e. hypertriglyceridaemia
types I, IV and V).
Thyroid function
Serum thyroxine was studied in 661 patients who were administered pravastatin in five
controlled clinical trials. From observations of up to two years in duration, no clear
association was found between pravastatin use and changes in thyroxine levels.
Impaired renal function: A single oral dose of pravastatin 20 mg was administered to 24
patients with varying degrees of renal impairment (as determined by creatinine
clearance). No effect was observed on the pharmacokinetics of pravastatin or its 3alphahydroxy isomeric metabolite (SQ 31,908). A small increase was seen in mean AUC
values and half-life (1.5) for the inactive enzymatic ring hydroxylation metabolite (SQ
31,945). Given this small sample size, the dosage administered, and the degree of
individual variability, patients with renal impairment who are receiving pravastatin should
be closely monitored.
Impaired hepatic function
HMG-CoA reductase inhibitors have been associated with biochemical abnormalities of
liver function. As with other lipid lowering agents, marked persistent increases (greater
than three times the upper limit of normal) in serum transaminases were seen in 1.3% of
patients treated with pravastatin in the US for an average period of 18 months. These
elevations were not associated with clinical signs and symptoms of liver disease and
usually declined to pretreatment levels upon discontinuation of therapy. Only two
patients had marked persistent abnormalities possibly attributable to therapy.
The significance of these changes, which usually appear during the first few months of
treatment initiation, is not known. In the majority of patients treated with pravastatin in
clinical trials, these increased values declined to pretreatment levels despite continuation
of therapy at the same dose. These biochemical findings are usually asymptomatic
although worldwide experience indicates that anorexia, weakness and/or abdominal pain
may also be present in rare patients.
As with other lipid lowering agents, liver function tests should be performed periodically.
Special attention should be given to patients who develop increased transaminase
levels. Liver function tests should be repeated to confirm an elevation and subsequently
monitored at more frequent intervals. If increases in alanine aminotransferase (ALT) and
aspartate aminotransferase (AST) equal or exceed three times the upper limit of normal
and persist, therapy should be discontinued.
Caution should be exercised when pravastatin is administered to patients with a history
of liver disease or heavy alcohol ingestion. Such patients should be closely monitored,
started at the lower end of the recommended dosing range, and titrated to the desired
therapeutic effect.
Skeletal muscle
Myalgia, myopathy and rhabdomyolysis have been reported with the use of HMG-CoA
reductase inhibitors. Uncomplicated myalgia has been reported in pravastatin treated
patients. Myopathy, defined as muscle aching or muscle weakness in conjunction with
increases in creatine phosphokinase (CPK) values to greater than ten times the upper
limit of normal, was reported to be possibly due to pravastatin in < 0.1% of patients in
clinical trials.
Rhabdomyolysis with renal dysfunction secondary to myoglobinuria has also very rarely
been reported with pravastatin. However, myopathy should be considered in any
patients with diffuse myalgia, muscle tenderness or weakness, and/or marked elevation
of CPK. Patients should be advised to report promptly unexplained muscle pain,
tenderness or weakness.
Pravastatin therapy should be discontinued if markedly elevated CPK levels occur or
myopathy is suspected or diagnosed. (Pravastatin therapy should also be temporarily
withheld in any patient experiencing an acute or serious condition predisposing to the
development of renal failure secondary to rhabdomyolysis, e.g. sepsis, hypotension,
major surgery, trauma; severe metabolic, endocrine, or electrolyte disorders; or
uncontrolled epilepsy.)
The risk of myopathy during treatment with another HMG-CoA reductase inhibitor is
increased with concurrent therapy with either fibrates, cyclosporin, erythromycin or
nicotinic acid. The use of fibrates alone is occasionally associated with myopathy. In a
limited size clinical trial of combined therapy with pravastatin (40 mg/day) and
gemfibrozil (1,200 mg/day) myopathy was not reported, although a trend towards CPK
elevations and musculoskeletal symptoms was seen. The combined use of pravastatin
and fibrates should generally be avoided.
Myopathy has not been observed in three post-transplant clinical trials which had
involved a total of 100 patients (76 cardiac and 24 renal). Some patients have been
treated for up to two years with pravastatin (10 to 40 mg) and cyclosporin, with or without
other immunosuppressants. In a separate lipid lowering trial involving 158 patients, no
myopathy has been reported with pravastatin in combination with niacin.
Endocrine function
HMG-CoA reductase inhibitors interfere with cholesterol synthesis and lower circulating
cholesterol levels, and, as such, might theoretically blunt adrenal or gonadal steroid
hormone production. Results of clinical trials with pravastatin in males and
postmenopausal females were inconsistent with regard to possible effects of the drug on
basal steroid hormone levels. In a study of 21 males, the mean testosterone response to
human chorionic gonadotrophin was significantly reduced (p < 0.004) after 16 weeks of
treatment with pravastatin 40 mg. However, the percentage of patients showing a
greater than 50% rise in plasma testosterone after human chorionic gonadotrophin
stimulation did not change significantly after therapy in these patients.
The effects of HMG-CoA reductase inhibitors on spermatogenesis and fertility have not
been studied in adequate numbers of patients. The effects, if any, of pravastatin on the
pituitary-gonadal axis in premenopausal females are unknown. Patients treated with
pravastatin who display clinical evidence of endocrine dysfunction should be evaluated
appropriately. Caution should also be exercised if an HMG-CoA reductase inhibitor or
other agent used to lower cholesterol levels is administered to patients also receiving
other drugs (e.g. ketoconazole, spironolactone, cimetidine) that may diminish the levels
of activity of steroid hormones.
Central nervous system toxicity
CNS vascular lesions, characterised by perivascular haemorrhage and oedema and
mononuclear cell infiltration of perivascular spaces, were seen in dogs treated with
pravastatin at a dose of 25 mg/kg/day, a dose that produced a plasma drug level about
50 times higher than the mean drug level in humans taking 40 mg/day. Similar CNS
vascular lesions have been observed with several other drugs in this class.
A chemically similar drug in this class produced optic nerve degeneration (Wallerian
degeneration of retinogeniculate fibres) in clinically normal dogs in a dose dependent
fashion starting at 60 mg/kg/day, a dose that produced mean plasma drug levels about
30 times higher than the mean drug level in humans taking the highest recommended
dose (as measured by total enzyme inhibitory activity). This same drug also produced
vestibulocochlear Wallerian-like degeneration and retinal ganglion cell chromatolysis in
dogs treated for 14 weeks at 180 mg/kg/day, a dose which resulted in a mean plasma
drug level similar to that seen with the 60 mg/kg dose.
Hypersensitivity
With lovastatin an apparent hypersensitivity syndrome has been reported rarely which
has included one or more of the following features: anaphylaxis, angioedema, lupus-like
syndrome, polymyalgia rheumatica, thrombocytopenia, leucopenia, haemolytic anaemia,
positive antinuclear antibody (ANA), erythrocyte sedimentation rate (ESR) increase,
arthritis, arthralgia, urticaria, asthenia, photosensitivity, fever and malaise. Although to
date hypersensitivity syndrome has not been described as such, in a few instances
eosinophilia and skin eruptions appear to be associated with pravastatin treatment. If
hypersensitivity is suspected pravastatin should be discontinued. Patients should be
advised to report promptly any signs of hypersensitivity such as angioedema, urticaria,
photosensitivity, polyarthralgia, fever or malaise.
Use in the elderly
Pharmacokinetic evaluation of pravastatin in patients over the age of 65 years indicates
an increased AUC. There were no reported increases in the incidence of adverse effects
in these or other studies involving patients in that age group. As a precautionary
measure, the lowest dose should be administered initially.
Use in children
Safety and effectiveness in individuals less than 18 years old have not been established.
Hence treatment in patients less than 18 years old is not recommended at this time.
Carcinogenesis, mutagenesis, impairment of fertility.
In a two year oral study of rats, a statistically significant increase in the incidence of
hepatocellular carcinomas was observed in male rats given pravastatin 100 mg/kg/day.
This change was not seen in male rats given 40 mg/kg or less, or in female rats at doses
up to 100 mg/kg/day. Increased incidences of hepatocellular carcinomas were also
observed in male and female mice dosed with pravastatin at 250 and 500 mg/kg/day, but
not at 100 mg/kg/day or less. An increased incidence of pulmonary adenomas was seen
in female mice dosed at 250 mg/kg/day. The AUC value for the serum concentration of
pravastatin at the no effect dose level of 100 mg/kg/day in mice was 5.5 times higher
than that in humans receiving pravastatin 40 mg/day.
The hepatocarcinogenic effect of pravastatin in rats is associated with proliferation of
hepatic peroxisomes. Other HMG-CoA reductase inhibitors (simvastatin and lovastatin)
also induce hepatic peroxisome proliferation and hepatocellular carcinomas in rats and
mice. The clinical significance of these findings is unclear.
In six genetic toxicology studies performed with pravastatin, there was no evidence of
mutagenic potential at the chromosomal or gene level.
In a study in rats with a daily dose up to 500 mg/kg, pravastatin did not produce any
adverse effects on fertility or general reproductive performance. The clinical significance
of these findings is not clear.
Use in pregnancy
Category D - Drugs which have caused, are suspected to have caused or may be
expected to cause an increased incidence of human foetal malformations or irreversible
damage.
HMG-CoA reductase inhibitors are contraindicated in pregnancy. The risk of foetal injury
outweighs the benefits of HMG-CoA reductase inhibitor therapy during pregnancy.
In two series of 178 and 143 cases where pregnant women took a HMG-CoA reductase
inhibitor (statin) during the first trimester of pregnancy, serious foetal abnormalities
occurred in several cases. These included limb and neurological defects, spontaneous
abortions and foetal deaths. The exact risk of injury to the foetus occurring after a
pregnant women is exposed to a HMG-CoA reductase inhibitor has not been
determined. The current data do not indicate that the risk of foetal injury in women
exposed to HMG-CoA reductase inhibitors is high. If a pregnant woman is exposed to a
HMG-CoA reductase inhibitor, she should be informed of the possibility of foetal injury
and discuss the implications with her pregnancy specialist.
Also see Contraindications.
Use in lactation
A negligible amount of pravastatin is excreted in human breast milk. Because of the
potential for adverse reactions in breastfeeding infants, if the mother is being treated
with pravastatin, breastfeeding should be discontinued.
Drug Interactions
Gemfibrozil: In a crossover study in 20 healthy male volunteers given concomitant single
doses of pravastatin and gemfibrozil, there was a significant decrease in urinary
excretion and protein binding of pravastatin. In addition, there was a significant increase
in AUC, Cmax and Tmax for the pravastatin metabolite SQ 31,906. Combination therapy
with pravastatin and gemfibrozil is generally not recommended.
Cholestyramine/colestipol: When pravastatin was administered one hour before or four
hours after cholestyramine or one hour before colestipol and a standard meal, there was
no clinically significant decrease in bioavailability or therapeutic effect. Concomitant
administration resulted in an approximately 40 to 50% decrease in the mean AUC of
pravastatin (see Dosage and Administration).
Cyclosporin: In a single dose study, pravastatin levels were found to be increased in
cardiac patients receiving cyclosporin. In a second multidose study in renal transplant
patients receiving cyclosporin, pravastatin levels were higher than those seen in healthy
volunteer studies. This does not appear to be a metabolic interaction involving P450
3A4.
Warfarin: With concomitant administration, pravastatin did not alter the plasma protein
binding of warfarin. Chronic dosing of the two drugs did not produce any changes in the
anticoagulant status.
Antipyrine: Clearance by the cytochrome P450 system was unaltered by concomitant
administration of pravastatin. Since pravastatin does not appear to induce hepatic drug
metabolising enzymes, it is not expected that any significant interaction of pravastatin
with other drugs metabolised by the cytochrome P450 system (e.g. phenytoin, quinidine)
will occur.
Other drugs: Unlike simvastatin and atorvastatin, pravastatin is not significantly
metabolised in vivo by cytochrome P450 3A4. Therefore, plasma concentrations of
pravastatin are not significantly elevated when cytochrome P450 3A4 is inhibited by
agents such as diltiazem and itraconazole.
In interaction studies with aspirin, gemfibrozil, nicotinic acid or probucol, no statistically
significant differences in bioavailability were seen when pravastatin was administered. In
other interaction studies, antacids (one hour prior to pravastatin) reduced and cimetidine
increased the bioavailability of pravastatin; these changes were not statistically
significant.
During clinical trials, no noticeable drug interactions were reported when pravastatin was
added to diuretics, antihypertensives, digitalis, angiotensin converting enzyme inhibitors,
calcium channel blockers, beta-blockers or nitroglycerins.
Adverse Reactions
Pravastatin is generally well tolerated. Adverse events, both clinical and laboratory, are
usually mild and transient. In all clinical studies (controlled and uncontrolled),
approximately 2% of patients were discontinued from treatment due to adverse
experiences attributable to pravastatin.
In seven randomised double blind, placebo controlled trials involving over 21,500
patients treated with pravastatin (N = 10,784) or placebo (N = 10,719), the safety and
tolerability in the pravastatin group was comparable to that of the placebo group. Over
19,000 patients were followed for a median of 4.8 to 5.9 years, while the remaining
patients were followed for two years or more.
Clinical adverse events probably or possibly related, or of uncertain relationship to
therapy, occurring in at least 0.5% of patients treated with pravastatin or placebo in
these long-term morbidity/ mortality trials are shown in Table 6.
Table 6 Percentage of patients with clinical adverse experiences in placebo controlled
trials
Cardiovascular
Angina pectoris
Disturbance rhythm (subjective)
Hypertension
Oedema
Mycocardial Infraction
Dermatological
Rash
Pruritus
Endocrine/metabolic
Sexual dysfunction
Gastrointestinal
Dyspepsia/heartburn
Nausea/vomiting
Flatulence
Constipation
Diarrhoea
Abdominal pain
Abdominal distension
Pravastatin
(n = 10, 784)
(%)
Placebo
(n = 10, 719)
(%)
3.1
0.8
0.7
0.6
0.5
3.4
0.7
0.9
0.6
0.7
2.1
0.9
2.2
1.0
0.7
0.7
3.5
1.4
1.2
1.2
0.9
0.9
0.5
3.7
1.6
1.1
1.3
1.1
1.0
0.5
General
Fatigue
Chest pain
Weight gain
Influenza
Weight loss
Weakness
Musculoskeletal
Musculoskeletal pain (including arthralgia)
Muscle cramp
Myalgia
Musculoskeletal trauma
Nervous
Dizziness
Headache
Sleep disturbance
Depression
Anxiety/nervousness
Paraesthesia
Numbness
Renal/genitourinary
Abnormal urination (includes dysuria and nocturia)
Respiratory
Dyspnoea
Upper respiratory infection
Cough
Sinus abnormality (includes sinusitis)
Pharyngitis
Special senses
Vision disturbance (include blurred vision)
Eye disturbance (includes eye inflammation)
Hearing abnormality (includes tinnitus and hearing
loss)
Lens opacity
3.4
2.6
0.6
0.6
0.6
0.5
3.3
2.6
0.7
0.5
0.5
0.6
5.9
2.0
1.4
0.5
5.7
1.8
1.4
0.3
2.2
1.9
1.0
1.0
1.0
0.9
0.5
2.1
1.8
0.9
1.0
1.2
0.9
0.4
1.0
0.8
1.6
1.3
1.0
0.8
0.5
1.6
1.3
1.0
0.8
0.6
1.5
0.8
0.6
1.3
0.9
0.5
0.5
0.4
Lens: In 820 patients treated with Pravastatin for periods up to a year or more, there was
no evidence that pravastatin was associated with cataract formation. In placebo
controlled studies, 294 patients (92 on placebo/control, 202 on pravastatin) were
evaluated using the Lens Opacity Classification System (a sophisticated method of lens
assessment) at six months and one year following the initiation of treatment. When
compared with the baseline evaluation, the final examination revealed the results in
Table 7.
Table 7 Lens evaluation results after one year of treatment
Lens opacity changes
Pravastatin
Number of patients (%)
(n = 202)
29 (14%)
Placebo/control
Number of patients (%)
(n = 92)
13 (14%)
No change
142 (70%)
63 (68%)
Worsened
31 (15%)
16 (17%)
Improved
There was no statistically significant difference in the change in lens opacity between the
control and pravastatin treatment groups during this time interval.
Comparative data indicate that pravastatin is 100-fold less potent than both lovastatin
and simvastatin (other HMG-CoA reductase inhibitors) in inhibiting cholesterol
biosynthesis in rat lens and 40-fold less potent than lovastatin in inhibiting cholesterol
biosynthesis in rabbit lens. Furthermore, unlike lovastatin and simvastatin, cataracts
have not been observed in animal studies (beagle dogs) when chronic oral doses of
pravastatin were administered for two years.
In three large placebo controlled trials, West of Scotland Study (WOS), Cholesterol and
Recurrent Events Study (CARE) and the Long-Term Intervention with pravastatin in
Ischaemic Disease Study (LIPID) (see Actions, Clinical trials), involving a total of 19,786
patients treated with pravastatin (N = 9,895) or placebo (N = 9,873), the safety and
tolerability profile in the pravastatin group was comparable to that of the placebo group
over the median 4.8 to 5.9 years of follow up.
The following effects have been reported with drugs in this class (not all the effects listed
have necessarily been associated with pravastatin therapy).
Skeletal: Myopathy, rhabdomyolysis, arthralgia.
Neurological: Dysfunction of certain cranial nerves (including alteration of taste,
impairment of extraocular movement, facial paresis), tremor, vertigo, memory loss,
paraesthesia, peripheral neuropathy, peripheral nerve palsy, anxiety, insomnia,
depression.
Hypersensitivity reactions: An apparent hypersensitivity syndrome has been reported
rarely which has included one or more of the following features: anaphylaxis,
angioedema,
lupus
erythematosus-like
syndrome,
polymyalgia
rheumatica,
dermatomyositis, vasculitis, purpura, thrombocytopenia, leucopenia, haemolytic
anaemia, positive ANA, ESR increase, eosinophilia, arthritis, arthralgia, urticaria,
asthenia, photosensitivity, fever, chills, flushing, malaise, dyspnoea, toxic epidermal
necrolysis, erythema multiforme, including Stevens-Johnson syndrome.
Gastrointestinal: Pancreatitis, hepatitis, including chronic active hepatitis, cholestatic
jaundice, fatty change in liver, and, rarely, cirrhosis, fulminant hepatic necrosis, and
hepatoma; anorexia, vomiting.
Skin Alopecia, pruritus. A variety of skin changes (e.g. nodules, discolouration, dryness
of skin/ mucous membranes, changes to hair/ nails) have been reported.
Reproductive: Gynecomastia, loss of libido, erectile dysfunction.
Eye: Progression of cataracts (lens opacities), ophthalmoplegia.
Laboratory abnormalities: Elevated transaminases, alkaline phosphatase and bilirubin;
thyroid function abnormalities.
Laboratory test abnormalities: Increases in serum transaminase (ALT, AST) values and
CPK have been observed (see Precautions).
Transient asymptomatic eosinophilia has been reported. Eosinophil counts usually
returned to normal despite continued therapy. Anaemia, thrombocytopenia and
leucopenia have been reported with HMG-CoA reductase inhibitors.
Dosage and Administration
Prior to initiating pravastatin, the patient should be placed on a standard cholesterol
lowering diet (American Heart Association (AHA) Phase 1 or NCEP Step 1) for a
maximum of three to six months, depending upon the severity of the lipid elevation.
Dietary therapy should be continued during treatment.
The recommended starting dose is 10 to 20 mg once daily at bedtime. In primary
hypercholesterolaemic patients with significant renal or hepatic dysfunction, and in the
elderly, a starting dose of 10 mg daily at bedtime is recommended. For maximum effect
pravastatin should be taken at bedtime on an empty stomach.
Since the maximal effect of a given dose is seen within four weeks, periodic lipid
determinations should be performed at this time and dosage adjusted according to the
patient's response to therapy and established treatment guidelines. The recommended
dosage range is 10 to 40 mg administered once a day at bedtime.
Pravastatin may be given in divided doses.
For the prevention of coronary heart disease in patients with hypercholesterolaemia the
dose is 40 mg per day as a single dose. The same dose is recommended for secondary
prevention of myocardial infarction in patients with average (normal) serum cholesterol.
In patients taking cyclosporin, with or without other immunosuppressive drugs,
concomitantly with pravastatin, therapy should be initiated with 10 mg/day and titration to
higher doses should be performed with caution.
Concomitant therapy.
Pravastatin has been administered concurrently with cholestyramine, colestipol, nicotinic
acid, probucol and gemfibrozil. Preliminary data suggest that the addition of either
probucol or gemfibrozil to therapy with lovastatin or pravastatin is not associated with
greater reduction in LDL cholesterol than that achieved with lovastatin or pravastatin
alone.
No adverse reactions unique to the combination or in addition to those previously
reported for each drug alone have been reported. Myopathy and rhabdomyolysis (with or
without acute renal failure) have been reported when another HMG-CoA reductase
inhibitor was used in combination with immunosuppressive drugs, gemfibrozil,
erythromycin, or lipid lowering doses of nicotinic acid. Concomitant therapy with HMGCoA reductase inhibitors and these agents is generally not recommended. (See
Precautions and Interactions.)
Overdosage
There has been limited experience with overdosage of pravastatin. To date there are two
reported cases, both of which were asymptomatic and not associated with clinical
laboratory test abnormalities. Of these two cases, one occurred in a clinical trial patient
who ingested pravastatin 3 g; the other ingested pravastatin 280 mg as marketed
tablets. Both cases also involved overdose of concomitant medications.
Treatment: Should overdose occur, treat symptomatically and institute supportive
measures as required.
Presentation
10mg: A yellow, oval, convex, sidewall scored tablet encoded “P 10”
20mg: A yellow, oval, convex, sidewall scored tablet encoded “P 20”
40mg: A yellow, oval, convex, sidewall scored tablet encoded “P 40”
Storage Conditions
Store below 25°C. Protect from light and moisture.
POISON SCHEDULE
S4
NAME AND ADDRESS OF SPONSOR
Real-RL
A Division of
GlaxoSmithKline Australia Pty Ltd
1061 Mountain Highway
Boronia Victoria 3155
™Pravastatin-RL is a trade mark of the GlaxoSmithKline group of companies.
Date of TGA approval: 17 November 2005
Date of most recent amendment: 2 May 2006
Issue 1